/**
 * A function that returns the x axis position for a dynamically generated
 * rollover.
 */
function getXaxis(realWidth, addInt) {
    var intPageWidth = (window.innerWidth) ? window.innerWidth : document.body.offsetWidth;
    var intPageLeft = (intPageWidth - realWidth) / 2;
	var intPageLeft = intPageLeft <= 0 ? 0 : intPageLeft;
	return intPageLeft + addInt;
}